Re: [RFC PATCH] drivers: power: Add watchdog timer to catchdrivers which lockup during suspend.

[Pavel Machek]

Hi!

> >> > do BUG which
> >> >    dumps stack of current task
> >> >    kills current task
> >> >
> >> > Current task may very well be idle task; in such case you kill the
> >> > machine. Sounds like you should be doing something else, like kill -9
> >> > instead of BUG()?
> >>
> >> Not much else you can do, you are stuck part way into suspend with a
> >> driver's suspend callback half executed.  All userspace tasks are
> >> frozen, and the suspend task is blocked indefinitely.
> >
> > Yes, there's better option. Attempt killing the [a]suspend task,
> > instead of killing the current task.
> 
> That will leave you in a completely undefined state.  If you just kill
> the task, you are likely to kill the synchronous suspend task, which
> is the task that would resume your drivers and unfreeze tasks.  That
> will leave you with no userspace tasks running, and much of your
> hardware suspended.  How is that a useful result?  If you somehow

So instead you kill random task? (BUG() from timer kills pretty much
random task, right?)

If you want to do panic(), do panic().
									Pavel
-- 
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